If you're struggling to keep up with your New Year's Resolutions, perhaps the issue isn't with you, but with the resolutions themselves. Did you set SMARTER goals, or just pick things you want to improve? If they were just pie in the sky promises, you may want to revamp them to make them better. You always want goals you set to be smarter.
If you just said, "I want to be healthier," that doesn't fit this goal setting blueprint. Think about what you actually mean when you say "healthier" and make some specific, measurable goals from that definition.
Following this standard will help you stay on top of your resolutions and feel good about the progress you're making.